What's so great about clogs?

Recently I've been seeing a ton of clogs on celebrities (from Ashly Olsen to Alexa Chung), and even more on the runway. I'm so confused -- I really don't get it (yet). I guess I must not fully understand the magnificence of the clog? Perhaps it's just a ploy of Holland's to increase traveling tourists? Or a joke on the fashion world?
Whatever it is, it's getting pretty popular...

Chanel Spring RTW 2010



Chanel Spring RTW 2010



Louis Vuitton Spring RTW 2010



Louis Vuitton Spring RTW 2010

I'm just as puzzled as you are....